Injection Of Isotonic Solution Research Articles

Влияние изменений водно-солевого баланса на ионо- и осморегулирующую функции почек у озерной лягушки

Changes in the water-salt balance and excretion of ions by the kidney after subcutaneous injections of hypertonic and isotonic NaCl solutions and dehydration were analyzed in lake frogs (Pelophylax ridibundus). The introduction of 0,75 M NaCl and dehydration for 1 hour increased the serum osmolality and Na+ and Cl– concentrations, and injections of isotonic solution did not affect these parameters. The applied treatments increased the level of Na+ and Cl– in the urine, and renal excretion of these ions. The most pronounced changes, including an increase in diuresis and glomerular filtration rate, were found after 0,75 М NaCl injection. In renal proximal tubules, changes in the pattern of the chloride channel (ClC-5), presumably involved in the process of protein endocytosis, were detected. An increase in the number of ClC-5-immunopositive tubule profiles and the intensity of the fluorescent signal in the apical cytoplasm of epithelial cells were revealed by immunohistochemistry and confocal microscopy. Studied effects of hypernatremia, hypervolemia and dehydration may be useful for further investigations of kidney function and mechanisms of epithelial tubular transport in frog models.

Reactivation of Silenced Transgene Expression in Mouse Liver by Rapid, Large-volume Injection of Isotonic Solution

Reactivation of Silenced Transgene Expression in Mouse Liver by Rapid, Large-volume Injection of Isotonic Solution

Immunohistochemical detection of 4-hydroxyaminoquinoline 1-oxide-DNA adducts in mouse tissues in vivo.

4-Hydroxyaminoquinoline 1-oxide (4HAQO)-DNA adducts were immunohistochemically demonstrated in the nuclei of various organs of mice with the use of an antibody directed against 4HAQO-modified DNA. Specificity of the immunostaining was confirmed by several tests, including preincubation of the antibody with 4HAQO-modified DNA or related molecules and digestion of the sections with DNase. 4HAQO dissolved in isotonic solution and injected sc into an isolated portion of the mouse skin clamped off with ring-shaped forceps resulted in dose-dependent generation of DNA adducts in the nuclei of epithelial cells, fibroblasts, and panniculus carnosus cells. Nuclear staining was absent in animals given injections of isotonic solution only, and the intensity of staining correlated well with the level of unscheduled DNA synthesis demonstrated autoradiographically. 4HAQO-DNA adducts were observed in all target organs of 4HAQO tumorigenesis (i.e., lung, trachea, pancreas, uterus, vagina, skin, and colon) after injection of the carcinogen. Nuclear staining was absent or low in nontarget organs, including the liver and brain. Considerable variation was found in staining levels between cell types and different anatomic locations of cells within each target organ. The intensity of immunohistochemical staining correlated well with numbers of 4HAQO-DNA adducts measured by the radiolabeling technique.

Hemodynamics of rapid injections of isotonic solutions

Hemodynamics of rapid injections of isotonic solutions

Excitation of medullary neurons by chemical agents.

Ventilatory responses and certain postural and autonomic responses were studied following injection of isotonic solutions of HCO3-, HPO4-, or citrate into the medullary reticular formation of decerebrated or anesthetized cats. In most respects the responses resulting from any of the three compounds are comparable to the effects of an electric stimulus applied in the same region. Attention was directed primarily to production of a state of ventilatory arrest (apneusis) and/or an alteration in minute volume of ventilation (Ve) by the compounds. Positive responses measured in this way were obtained in roughly 75% of trials. Apneusis in inspiration or expiration was usually followed by either an increase or decrease in Ve. Variations in the pH of the solutions from 6.5 to 8.2 by the addition of CO2 or by HCl failed to alter significantly the ventilatory responses. Also, 1.5% citrate was a less effective stimulus to produce apneusis than 3% citrate, 3.6% phosphate, or 1.3% bicarbonate. After the period of apneusis, ventilation was increased in 55% of trials when 1.5% citrate was used; however, with 3% citrate a decrease in ventilation was more frequently observed. It is proposed that this action of all three compounds is related to their property to reversibly bind calcium ions.